Originating (presumably) on the World of Warcraft forums, this is an essentially derogatory concept some people employ that means that all that a certain class must do in order to achieve success in the game is to bind every key on their keyboard to one ability that is perceived to be overpowered, and then continue to roll their face across the keyboard. The notion is that this one ability is so amazingly overpowered in relation to those of other classes, all one has to do is absently spam it as much as possible (and they might as well do it with their face, because there isn't any other use for the big stupid thing on top of their shoulders).

Background: when someone alleges a World of Warcraft] class is either A) very simple to play, requiring no attention to dps rotation or B) has a hugely overpowered ability that compromises a unfair % of their DPS done.

In those situations, you, the alleged simpleton, would then keybind your entire keyboard to one or two abilities, carefully place left cheekbone on the W key, and while maintaining consistent pressure between your face and keyboard, roll your lips, nose, right cheekbone to about the L key, and then backwards to the W key, and then repeat.

DENOTATION
a faceroll is when playing a video game, to use one's face on the keyboard to play the game instead of using one's hands.

(See alternate definition for etymology relating to World of Warcraft and one very specific meaning.)

CONNOTATION

This is a hyperbolic, humorous term used to imply that certain kinds of play are overpowered (i.e. unfair), very easy (again in contrast to others), or are marked by being devoid of any strategy. That is to say, you can play the game successfully (1) without looking at the screen and (2) by hitting random keys (with your face.)

The term faceroll can be used as generally derogatory or inflammatory, as it is essentially a personal attack devaluing the video game developers's judgment.

Evolution of the use of the term into gamer lexicon demonstrates the term can simply be used humorously as an absurdity (to alleviate tension rather than create an indictment.)

--In context of World of Warcraft--

"I played a Paladin once. I started playing, and then rolled my face over the keyboard. When I looked up, I was in Outland."

(This comment suggests that 1/3 of the game content can be completed using a Paladin character in one faceroll. This comment is witty and humorous as an absurdity, because it would take ~50-60 hours of play time to complete this task.)

"We don't need to use crowd control in this dungeon. We can just faceroll it."

(This player is arguing that the dungeon is so easy, the group doesn't need to pay attention to what they are doing.)

faceroll - is the term used to define an arena team's make-up of same class toon. Many teen and kids have associated keyrolling or pwning to be the same thing as facerolling. In 2005, if you asked for a faceroll 5's team it meant you want the same class make-up for the whole team. You can not faceroll someone in a duel you can only pwn them.

Druid: We just facerolled you.
Pally: No you didn't, you barely won.
Druid: No kid, FaceRolled as in a team of boomkins